The invention of this application relates to a pressurized fluid dispensing apparatus. More particularly, this invention relates to such an apparatus for use where a directed stream of fluid can be controlled in, for example, a subgingival irrigation system.
Various fluid dispensing pumps and sprayers have been previously suggested. Keyes et al, U.S. Pat. No. 4,700,872, describes a pump for dispensing liquid via a syringe in which a hollow cylinder is mounted. The cylinder is connected to the chamber by a first normally closed check valve. A hollow plunger, which receives a liquid charge, reciprocates in the cylinder and is connected thereto by a second normally closed check valve. On the out-stroke of a piston, the liquid in the piston is sucked through the second normally closed check valve into the cylinder and, on the instroke of the plunger, the liquid is forced through the first normally closed check valve into the chamber wherein it is maintained under pressure created by the pumping action of the plunger. An outlet tube leads from the lower part of the chamber to a syringe and a normally closed pinch valves in the syringe is manually operable to permit liquid under pressure to be squirted from the syringe.
Spengler et al, U.S. Pat. No. 4,537,334, describes a reinforced plastic bottle or vessel with a relatively large neck with buttressed threads and a beveled rim on its neck onto which threads is screwed a cap assembly. The cap assembly comprises a plastic cap base member having an integral handle and a nozzle connection, a plastic manual air pump, a plastic siphon, a valve and spray nozzle assembly, and a leer to operate the valve. The air pump is supported by an integral flange and it depends vertically from the cap base member into the bottle with a disc-type check valve at its bottom.
Cohen, U.S. Pat. No. 4,175,704, describes a non-aerosol type spray device comprising a container for housing a liquid material to be dispensed and a plunger slidable as a piston within the container and an elongate tubular member for actuating the plunger with a bore extending continuously therethrough for communication with the interior of the container at one end. There is additional communication with a spray nozzle at the other end for passage of the liquid material from the container through the bore to the spray nozzle in response to displacement of the plunger.
Genese, U.S. Pat. No. 4,036,232, describes an aspiration unit which affords a uniform suction level for aspirating fluids from body cavities. The unit comprises a double piston member, a first head of which is in sealing engagement with a syringe barrel and the second head of which is oppositely disposed and contained in a telescoping member which is also receivable in the syringe barrel. Upon movement of the telescoping member outwardly from the syringe barrel, a vacuum will be created in the telescoping member as well as in that portion of the barrel member between the first piston member and the nozzle which is closed from the atmosphere by means of a valve. Upon insertion of a flexible tube into a body cavity and opening of the valve, fluid will be aspirated into the syringe barrel by means of the partial vacuum created in the syringe barrel and in the telescoping member.
Rodrigues, Jr., U.S. Pat. No. 3,191,807, describes a liquid dispensing device for dispensing ultra-micro volumes of liquid. The dispensing device comprises a syringe having a longitudinal passageway for a piston assembly and includes an enlarged recess at its upper end. The passageway leads to an intake-discharge member. The flow into the chamber is controlled by an intake valve assembly and a discharge valve assembly controls flow from the chamber. The piston assembly in the passageway has a piston adapted to alter the effective volume of the intake-discharge chamber during reciprocation. The stroke of the piston assembly is adjustably controlled by a plunger.
Esmay, U.S. Pat. No. 2,880,939, describes a device for spraying liquid materials in a finally divided or atomized form. The spraying device comprises an outer, elongated cylindrical tube made of transparent material and plunger supply tube also made of a transparent material loosely telescoped within the upper end of the outer tube and having a length of the same order of magnitude as the outer tube. The plunger tube contains the material to be sprayed and the bottom of the plunger tube contains a spring-urged valve assembly which, when the plunger tube is fully extended into the outer tube, fully opens to dispense a fixed quantity of material into a receiving well at the bottom of the plunger tube.
Pollak, U.S. Pat. No. 2,743,847, describes a mixing and dispensing apparatus for mixing and dispensing a liquid antiseptic with quantities of water. The apparatus consists of a cylindrical container which is adapted to be secured to a water outlet and which contains a main mixing and water storing chamber, a liquid chemical storage chamber mounted above the mixing chamber, means for dispensing and mixing a measured quantity of liquid chemical solution of water in the main chamber and control means controlling the entry of water and discharge of a mixture of water and liquid chemical solution, respectively.
Hein, U.S. Pat. No. 1,563,627, describes a hypodermic syringe construction wherein the solution to be ejected is adapted to be contained within a vial or ampule which is used as a piston within the syringe in filling the syringe and ejecting the fluid therefrom.
Leitch, U.S. Pat. No. 1,220,243, describes a flush tank for dental use where a manually-operable pump pressurizes fluid in a reservoir. However, an output conduit is attached at the top of the reservoir through a vacuum jacket, above the fluid level, and extends into the fluid in the reservoir. There is no output opening in the reservoir below the fluid and no output valve which would allow an output conduit to be connected and disconnected.
Heretofore, none of the prior art fluid dispensing devices embodied a simplified apparatus for providing a directed stream of fluid where an output conduit could selectively be connected to a reservoir or where an output valve maintains pressurized fluid in the reservoir when the conduit was not connected. The invention described in this application is directed to a pressurized fluid dispensing apparatus which overcomes problems in prior fluid dispensing devices and is able to precisely and controllably supply solutions in dentistry, medicine, veterinary medicine, industrial and commercial fabrications and various other uses.